First of all stability criteria are different with different airlines. We have the gate at 1000' both in VMC and IMC, so at 700' we would be below it allready. Second, the 737 is certified for flaps 30 OEI landings including CAT IIIa depending on variant so a change of configuration would not be required to begin with, even less so in VMC with a clear runway in front and a landing clearance received.